This invention relates to tranexamic acid-containing oral compositions having a good feeling to use.
Tranexamic acid is a well-known anti-inflammatory and hemostyptic agent. It is proposed in Japanese Patent Publication No. 49-39818 to incorporate tranexamic acid into oral compositions such as dentifrices because tranexamic acid is effective for periodontosis propylaxis.
However, as tranexamic acid inherently tastes bitter, oral compositions containing it are bitter and rough to the palate, giving an undesired feeling when orally applied in practice.
An additional disadvantage of such tranexamic acid-containing oral compositions is that they are unstable and tend to discolor upon aging. It was proposed to add cyclodextrin to tranexamic acid-containing oral compositions to prevent discoloration. In general, known techniques for preventing the discoloration of oral compositions such as dentifrices include the addition of a chelating agent or a polycarboxylic acid derivative. However, these approaches have been unsuccessful. When cyclodextrin is blended in an oral composition, a flavor coexisting in the composition is chemically included by cyclodextrin to reduce the flavoring effect, and as a result, this composition fails to give a refreshing feeling to the mouth when applied thereto. Another problem is a reduction of the net amount of active antiplasmin tranexamic acid due to chemical inclusion of tranexamic acid by cyclodextrin. Further, when a chelating agent or a polycarboxylic acid derivative is blended, a consideration is to be made so as to minimize the absorption of calcium ions by these compounds acting on teeth.